I have. At this point not. Ordered military. Engagement in the situation but the point that you made about. Chemical biological weapons. It's critical that's an issue that doesn't just concerned Syria -- concerns. -- close allies in the region including Israel. -- concerns us. We cannot have a situation -- chemical or biological weapons are falling into the hands of the wrong people. We have been very clear to the outside regime but also to. Other players. On the ground. That. A red line for us is. We start saying. A whole bunch chemical weapons moving around -- -- That would change my calculus that would change my question.

This transcript has been automatically generated and may not be 100% accurate.

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